High Country Conservation Center climate action director Jess Hoover first started to notice the hot streak on the last day of September, when she was trying to figure out how to dress for the day.

The forecast called for a high temperature of 67 degrees that day — balmy for an autumn day at 9,000 feet in the Colorado Rocky Mountains. Then, throughout October, when Summit County’s ski resorts usually start to open, Hoover found herself wearing T-shirts, basking in warm sunshine and encountering little to no snow on her trail runs.

“Every day when I was looking at it, the forecast was really far above average,” Hoover said. “It was beautiful, but I knew it wasn’t normal. It’s not normal in Summit County to have a 75 degree day in October.”

Statewide, this past October was the second hottest on record and the hottest in 50 years, according to the Colorado Climate Center. In Summit County, average temperatures were 7 degrees warmer than normal throughout the entire month.

On Oct. 3, the temperature hit 71 degrees in Summit County, tying the record for that day set in 1952, according to the National Weather Service. Then, two days later, on Oct. 5, the temperature hit 75 degrees, shattering the previous record high of 72 degrees set in 1958. Another two days passed, and the weather station in Dillon recorded a high temperature of 72 degrees, tying the all-time record high for that date set in 1954.

As records were toppled, Hoover began tracking daily temperatures in a spreadsheet. Working in climate advocacy, she knew that it isn’t possible to point to any single day’s weather and conclude it was caused by climate change.

But as the unseasonable warmness continued day after day in October, she said it became hard to separate it from the global warming trend that is making Colorado — and the rest of the world — hotter.

“With climate change in particular, I think the reason why it can be hard to grab onto, why it might go unnoticed by people, is because it is gradual,” Hoover said. “It’s an incremental change. So, it can be hard from one year to the next to really pay attention to that and point it out.”

For decades, humans have been burning fossil fuels that release heat-trapping gasses like carbon dioxide into the atmosphere, creating the greenhouse effect that is warming global temperatures.

In fact, no region in the U.S. is cooler than it was during the 20th century, according to the National Oceanographic and Atmospheric Administration. Average temperatures in Colorado have increased 2 degrees over the past 30 years, with an additional 2 to 5 degrees of warming expected by 2050.

Summit County Sheriff Jaime FitzSimons said that he was biting his nails as temperatures reached 75 degrees some days in October because, in Summit County, warm temperatures bring an increased risk of wildfire.

“When you talk about a community-wide threat, there’s no doubt that wildfires are our No. 1 threat,” FitzSimons said. “A catastrophic wildfire would absolutely impact the entire community and for decades to come. If this place burned down, why would you come visit Summit County?”

Across the western U.S., climate change has led to longer fire seasons and larger, more destructive fires. Today, the average core wildfire season is 78 days longer than it was in the 1970s, according to the Colorado Division of Fire Prevention and Control.

FitzSimons said that he has seen the winter season shrink in Summit County over the years, leading to longer fire seasons, especially when there is less snow on the ground in the fall or the spring.

“When I moved here 20 years ago, boy, it started snowing around Labor Day, sometimes it snowed certainly past the 4th of July,” FitzSimons said. “So our fire season used to be a lot shorter. Now, 20 years later, I’m the sheriff who is responsible for these wildfires. Wildfire season, as I see it now, goes from snow melt to snow fall.”

In October, Summit County entered Stage 1 fire restrictions due to the dry, hot weather. Then, on Oct. 23, a small wildfire sparked north of Interstate 70 in Frisco. Firefighters later determined that the fire had been human caused.

FitzSimons said that as the climate continues to warm, it is imperative that the county continue its wildfire mitigation work, like pile burnings and clear cutting to create fire breaks along the wildland-urban interface. Maintaining close partnerships with firefighting partners at the state and federal level will also be critical, he said.

Climate change is not slowing down but there is hope, Hoover said. One of the biggest steps people can take is simply to talk about climate change because that helps to normalize conversation about the collective challenges the community faces, she said.

But there are also other steps everyday citizens can be taking from writing to their elected representatives to thinking ahead so that the next time they need to buy a new vehicle or appliance, they are ready to choose a green option.

“The hope is that we have agency,” Hoover said. “We know what we need to do. The solutions are available, so we just have to work harder to make it happen.”